Imran Rashid

Circuit Switching and Packet Switching

There are two fundamental approaches to moving data through a network of links and switches: circuit switching and packet switching. In circuit-switched networks, the resources needed along a path (buffets, link transmission rate) to provide for communica... Read >

File Transfer Protocol: FTP

In a typical FTP session, the user is sitting in front of one host (the local host) and wants to transfer files to or from a remote host. In order for the user to access the remote account, the user must provide a user identification and a password. After... Read >

History of Computer Networking and the Internet

You should know enough now to impress your family and friends! However, if you really want to be a big hit at the next cocktail party, you should sprinkle your discourse with tidbits about the fascinating history of the Internet [Segaller 1998]. The ... Read >

How Do Packets Make Their Way Through Packet-Switched Networks?

Earlier we said that a muter takes a packet arriving on one of its attached communication links and forwards that packet on to another of its attached communication links. But how does the router determine the link onto which it should forward the packet?... Read >

ISPs and Internet Backbones

We saw earlier that end systems (user PCs, PDA's, Web servers, mail servers, and so on) connect into the Internet via an access network. Recall that the access network may be a wired or wireless local area network (for example, in a company, school, or li... Read >

Messages, Segments, Datagram’s, and Frames

The physical path that data takes down a sending end system's protocol stack, up and down the protocol stacks of an intervening link-layer switch and router, and then up the protocol stack at the receiving end system. As we discuss later in this book, rou... Read >

Wireless Access

Accompanying the current Internet revolution, the wireless revolution is also having a profound impact on the way people work and live. Today, more people in Europe have a mobile phone than a PC or a car. And the wireless trend is continuing with many ana... Read >

Application-Layer Protocols

We have just learned that network processes communicate with each other by sending messages into sockets. But how are these messages structured? What are the meanings of the various fields in the messages? When do the processes send the messages? These qu... Read >

Cleaning Windows XP: Getting Started

You can do quite a bit to clean the average Windows XP system. Files proliferate, programs fall out of favor, viruses reproduce, e-mail clusters, and pop-ups populate. Throw in a little system neglect and before you know it, you have a messed-up system th... Read >

When should you upgrade to Vista?

If you have a PC with Windows XP installed, and it works well enough for what you want to do, leave it alone. Keep your Windows XP machine updated with the latest security patches, as soon as they're tested and found to be reliable. But don't throw it in... Read >

What is Windows Vista?

Windows Vista is a type of software known as an operating system (abbreviated OS). One thing that's unique about an operating system is that it's the only software that a computer is required to have. If you try to start a computer that has no operating ... Read >